package com.huaao.micropolice.root.commons;

import org.springframework.context.ApplicationContext;  
import org.springframework.context.ApplicationContextAware;

/** 
 * 以静态变量保存Spring ApplicationContext, 可在任何代码任何地方任何时候中取出ApplicaitonContext. 
 *  
 */  
public class SpringContextHolder implements ApplicationContextAware {
	
	private static ApplicationContext applicationContext;

	/**
	* 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量. 
	*/  
	public void setApplicationContext(ApplicationContext applicationContext) {  
		SpringContextHolder.applicationContext = applicationContext; // NOSONAR  
	}  
  
	/** 
	* 取得存储在静态变量中的ApplicationContext. 
	*/  
	public static ApplicationContext getApplicationContext() {  
		checkApplicationContext();  
		return applicationContext;  
	}  
  
	/** 
	* 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型. 
	*/  
	@SuppressWarnings("unchecked")  
	public static <T> T getBean(String name) {  
		checkApplicationContext();  
		return (T) applicationContext.getBean(name);  
	}  
  
	/** 
	* 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型. 
	*/  
	@SuppressWarnings("unchecked")  
	public static <T> T getBean(Class<T> clazz) {  
		checkApplicationContext();  
		return (T) applicationContext.getBeansOfType(clazz);  
	}  
  
	/** 
	* 清除applicationContext静态变量. 
	*/  
	public static void cleanApplicationContext() {  
		applicationContext = null;  
	}  
  
	private static void checkApplicationContext() {  
		if (applicationContext == null) {  
			throw new IllegalStateException("applicaitonContext未注入,请在applicationContext.xml中定义SpringContextHolder");  
		}  
	}  
}  